Answered By: Anne Greenshields Last Updated: Sep 27, 2018 Views: 61
As you are aware the principle is that you should always make an effort to find the original source. However, if it is not available to you then you must not pretend you have read it. Only cite the source that you have accessed in the bibliography, not the secondary citation.
Secondary Citation Rule 1.3 is on the AGLC Referencing Guide and gives many ways of citing/referencing material quoted in another source.